Ignition apparatus



July 3l, 1923. 1,463,197

. o. F. CONKLIN IGNITION APPARATUS FiledSepb. 19 1917 Patented July 31,.1923.

UNITED STATES PATENT OFFICE.

OLIVER F. CONKLIN, 0F DETROIT, MICHIGAN, .LSSIG-NOR TO REMY ELECTRIC COMPANY, 0F ANDERSON, INDIN, A CORPORATION OF INDIANA.

IGNITIoN APPARATUS.

Application led September 19, 1917.

To all whom it may concern.'

Be it known that I, OLIVER F. CONKLIN, a citizen of the United States,residing. at Detroit, in the county of Wayne and State of Michigan, haveinvented certain new and useful Improvements in Ignition tus, of whichthe following is a full, clear, and exact description.

This invention relates to certain new and usefulimprovements in ignitiondevices and more particularly to improvements in the breakery devicesfor the primary ignition circuit, which device is commonly called thetimer. Other improvements reside in the provision of a novel camadvancing mechanism which is adapted to advance the time of ignition inaccordance with changes in engine speed. The improvements in the sparkadvancing mechanism provide a structure which is adapted to produce theproper spark advance for a wide range of engine speed and powerconditions. Furthermore, the spark advancing device is reversible, sothat by a slight rearrangement it may be made to operate in either aclockwise or counter-clockwise direction of rotation.

With these and other objects in View which will be pointed out more indetail in the accompanying specification and claims, the preferredembodiment of the invention Will now be described.

In the drawings:

Fig. 1 shows in central section a timer distributor having the improvedbreaker devices and spark advancing mechanism.

Fig. 2 shows a top plan view of the breaker structure mounted upon itssupporting plate and in operative relation to the timer cam.

Fig. 3 shows a top plan view of the spark advancing mechanism with theparts in the position they occupy when the timer is at rest. y

Fig. 4. shows the position of the spark advancing mechanism parts infully advanced position.

In more detail in the drawings, 10 is 'the timer casing having dowels 11to locate the timer plate 12 and the distributor cap 18. The distributoris referably of the type shown in Conklin atentv No. 1,372,065, issuedMarch 22, 1921, and is secured to the casing by means of the springclips 14. The engine driven shaft 15 is journalled in the Appara-lSerial No. 192,057.

depending part of the easing and at its upper end the shaft has securedthereto to rotate in unison therewith a circular plate 16. Three'equally spaced pins 17 are carried by this plate and project upwardlytherefrom to form the pivots for three centrifugal weights 18. Each ofthese weights carries a rivet member 19 rounded at each end so as toform a frictionless support for the weight upon the plate 16 and topermit each weight to move about its pivot without bending. To reducethe friction 'to a mini mum, preferably the Weight rivet and the plateare both hardened. The weights are preferably spaced from the plateadjacent the pivots by washers 20.

Coaxial with the engine shaft 15 and preferably integral therewith is ashaft 21 which extends above the plate 16 and the plane of weights 18.This shaft forms a bearing or journal for a sleeve member 22 to which isattached a spider member having three arms 23. Also attachedjto thesleeve is a timer cam 24. Each centrifugal weight 18 has a 'tail piece25 which projects in toward the center of the shaft 21 and cooperateswith a cam edge 26 on the spider arms 23. Each spider arm 23 has ltwosymmetrical cam edges 26 and this permits the weights to be turned overso that the tail pieces will cooperate with the opposite sides of thespider (see dotted line construction in Fig. 3). This permits the sameparts to be used with either a clockwise or counterclockwise rotation.The spider arms 23 each carry pins 27 which form supports for springs28, which at opposite ends connect with pins 17. The pins 27 projectthrough the spider arm into arcuate slots 29 of the plate 16. The pins27 cooperate with the end of the slots 29 and limit the extreme outwardmovement of the weights (See Fig. 4). The eXtreme inward movement orposition. of the weights is limited by the rear edges of the tail piecescontactingwith the edges of the weights (see Fig. 3

With a centrifugal evice for advancing the spark, the centrifugal forceincreases as the square of the radius of the mass center from the centerof rotation and also directly as the speed increases. From an inspectionof Fig. 3 it will be seen that the line of action of springs 28 isradial, in which direction they exert little restraint upon the outwardmovement of the weights; also the I tail pieces exertA their greatestleverage upon the spider arms. As the weights move outwardly, the tailpieces cam against the cam edges 26 of the spider'arms 23 and advancethe spider sleeve and time-r cam 24 angularly with respect to the engineshaft. In this Way the spark advance is effected. .As the spider isadvanced, the springs' 28 act' in a manner so as to effect a greater andgreater restraint upon the advance of Athe spider.

-Uoncu'rrently also tail pieces 25 exert less and less leverage on thespider cam edges 26, and by these coacting meansthe excessively greatcentrifugal advancin actlon is compensated for. f l! urthermore, t espark advance for a particular set of engine conditions can becontrolled by changing the contour. of the cam edge 26 of the spiderarms 23, or byl changing the contour of the coacting edges of the tailpieces 25. Once thel roper contour is determined for a particu arengine' the parts may he easily duplicated and the spark advance will bethe vsame for each complete apparatus. It will so as to obtain adirectrollingcontact, Whereby friction Will be reduced.

Timer commotion.

The timer or breaker comprises a base lplate 30, preferably a stamping,which is securedto plate 12 but insulated therefrom by means of a stripof insulation 31. The base plate 30 has an integral struck up portion 32to which is secured a strip of insulating material 33, such as Dilecto.This strip 33 forms the fulcrum for the breaker lever 34,- which ispreferably of sheet metal and 'formed into a channel section so as to berigid and very light in weight. A copper strap or jumper 35 conducts thecurrent from the insulated Vbase plate 30 to the breaker lever 34. Thebase plate 30 also has struck up posts 36 and 37, one of which, namely36, forms an abutment to support the breaker lever when theplate() 1sre-' moved, and the other-,namely post 37 forms 'an abutment to whichthe other end of acoil spring 39 is attached. The opposite end y of thecoil spring is attached to an eye in the breaker lever, whereby contact40 carried by the lever is normally maintained in contact withtheadjustable contact 41. This adjustable contact is carried by a ost 42struck up .from a plate 43 which is astened to and in electricalconnection with base plate 12. A screw (shown in Fig. 2) secures theplate 43 to the base plate.

In order to move the breaker lever against the action of the restrainingspring in order to periodically open the primary ignition circuit at thecontacts 41 and 40, the end 44 of the breaker lever is bent over at anangle and carries a piece of insulating maternal, such as Dilecto, whichl'normally is in practically tangential contact with cam 24. As the camrotates the breaker lever is rocked about its fulcrum to effect a breakof the circuit at the contacts 40,` 41. The breaker lever is a lever ofthe second order the cam supplies the -forceat the free end of the'lever'while the spring (weight element) is located between the cam andthe fulcrum. I Q

The spring 39 therefore maintains the lever upon its fulcrum in eitheropen or closed position of the cam. The strap 35 operates in conjunctionwith the spring and the action of `the camA upon the rubbing block tomaintain the lever upon its fulcrum.

A certain pressure between the timer con-l tacts is alwaysrequiredinonder to insure How' of current during the time of make ofthe' ignition circuit. This is produced by the action of a spring. As aresult, this spring produces pressure between the cam and rub ing blocktending to wear the surfaces of both and particularly the latter. Byplacing the contacts between the rubbingblock and the breaker leverfulcrum, the pressure of the 'rubbing block upon the cam is much lessthan where the rubbin block is located between the lcontacts an thefulcrum. Therefore by virtue of the construction and arrangementdescribed, the wear on the rubbin block is reduced.

vThe condenser W ich is used to minimize the sparking at the contacts,is preferably contained in a metal case secured to the base plate at oneside of the cam. One side of the condenser within thec'ase is connectedto plate 30 by a strap 47, and the other vside o'f the condenser isgrounded on the base plate.

The hi h need not described Ahere iii detai as it is fully described inthe application heretofore referred/ to. y block is a block ofinsulating material and carries the distributor sion electric currentWhat I claim is:

1:.A timer for ignition ap aratus comprising a rotatable cam,.a brea erlever fulcrumed at one end upon a fixed part, and

tension distribiiting a paratus It is suflcient to state that f or thehigh .ten-

cooperating at its opposite end with the rotatable cam, a stationarycontact carried by a iiXed part and located between the cam and fulcrum,a cooperating contact carried by the breaker lever and disposed betweenthe ends thereof, and a retractile coil spring for normally maintainingthe contacts in engagement fastened at 4one end to a ixed part and atits other end to the breaker lever, the point of'fastening beingintermediate the contacts and the fulcrum of the lever, whereby thespring will maintain the lever uponits fulcrum in either the open orclosed position of the contacts.

2. A timer for ignition apparatus comprising a rotatable cam, a breakerlever fulcrumed at an end remote from the timer cam and having a blockat the opposite end disposed obliquely to the plane of the breakerlever, said block adapted to rub on said rotatable cam and extendingsubstantially tangential thereto, a stationary contact, and acooperating movable contact disposed on the breaker lever between thefulcrum and the block, and a retractile coil spring attached to thebreaker lever intermediate the contacts and the fulcrum thereof formaintaining the rubbing block in vproximity to the cam and the contactsnormally closed except when opened by the cam, for maintaining the leverupon its fulcruin in either the open or closed position of the contacts;and a exib'le strap connected to a fixed part and to the lever, saidstrap operating v1n conjunction with the operation of the cam upon th'eblock to maintain the lever upon its fulcrum.

3. A timer for ignition apparatus comprising a rotatable cam, a breakerlever fulcrumed at an end remote from the cam and having a block at theopposite end disposed obliquely to the plane of said lever, said blockadapted to rub on said cam and extending tangential thereto, cooperatingtimer contacts one of which is carried by the lever, a spring connectedwith the lever for maintaining the contacts normally in engagement, aflexible strap connected With the lever and a fixed part, said springand strap operating in conjunction with the action of the cam u on theblock to maintain the lever upon its ulcrum.

4. A timer for ignition apparatus coinprising a rotatable cam, a breakerVlever of the second order having one end cooperating with said cam, acoiled retractile spring fastened to said lever intermediate its endsand to a fixed part of the ignition apparatus, a contact carried by saidlever intermediate the ends thereof, a cooperating contact, saidcontacts being normally closed by the said spring and being periodicallyopened to interrupt the primary circuit therethrough by the cam actingupon the breaker lever.

5. A timer for ignition apparatus com prising a rotatable cam, a baseplate, a subvbase plate fastened thereto, a plurality of postsprojecting upwardly therefrom, one of said posts carrying a blockforming a fulcrum for a breaker lever, a second of said posts forming asupport for one end of a spring, a third of said posts forming alim!iting abutment for said breaker lever, a second sub-base plate carryingla contact, a breaker lever fulcrumed at one end on the aforesaidfulcrum-block' and contacting at its opposite end with the rotatablecam, a contact on' said breaker lever cooperating with the aforesaidcontact, and airetractile spring connecting the breaker lever and theaforesaid post and normally maintaining the contacts closed except whenopened by the action of the cam on the breaker lever 6. lin an ignitionapparatus, the combination with an engine driven shaft; of a timer camadapted to be advanced angularly relatively thereto; centrifugal Weightdevices pivoted on a member attached to the engine driven shaft, andprovided with tail pieces; a spider carrying the timer cam and providedwith camming surfaces cooperating with said tail pieces, said surfacesand tail pieces being arranged so that the point of action therebetweenmoves toward the axis of the spider vas the weights move outwardly withincreasing speed; and coiled springs connecting the spider with saidmember, said springs being arranged so that the leverage thereof withrespect to the spider substantially increases as the weight members moveoutwardly from the shaft.

7. In an ingition apparatus, the combi nation with an engine drivenshaft; of a timer cam adapted to be advanced angularly relativelythereto; centrifugal Weight devices pivoted on a member attached to theengine driven shaft, and provided with tail pieces; a spider carryingthe timer cam and provided with camming surfaces cooperating with saidtail pieces, said surfaces and tail pieces being arranged so that thepoint of action therebetween moves toward the axis of the spider as theweights move outwardly With increasing speed; and coil springsconnecting the spider and said member, said `springs being arrangedsubstantially radially with respect to the axis of the spider, wherebyinitially to exert comparatively little restraining. force upon theadvancing movement of the spider.

8. lin an ignition apparatus, the combination with an engine drivenshaft; a weight supporting member carried by said shaft; a plurality ofcentrifugal weights having camming portions mounted upon studs carriedby said member; a timer cam journalled for rotation axially of saidshaft; radially extending camming arms connected with said timer cam andcooperating with said camiiiing portions, said portions and arms beingarranged so that as the weights move outwardly from the cam, the

points of action between said portions and said arms Will move towardthe cam axis; and coil springs connecting said arms with said studs,said springs initially extending substantially radially with respect tothe' cam axis, whereby initially to exert comparatively littlerestraining force upon the advancing movement of the spider.

9. In an ignition apparatus, the combination with an engine drivenshaft; a weight supporting member carried by said shaft; a plurality ofcentrifugal weights having camming portions mounted upon studs carriedby said member; a cam advancing spider mounted upon said shaft forangular displacement relatively thereto and provided with radiallyextending camming arms, said arms and said camming portions of theweights being arranged so that as the weights move outwardly from thecam, the points of action between said portions and said `arms will movetoward the cam axis; and coil springs connecting said arms with saidstuds, said springs initially extending substantially radially withrespect to the cam axis, whereby initially to exert comparatively littlerestraining force upon the advancing movement of the spider.

10, In an ignition apparatus, the combination with an engine drivenshaft; a weight supporting member carried b y said shaft; a plurality ocentrifugal weights having camming portions pivotally mounted upon saidmember; a timer cam journalled for rotation axially of said shaft;outwardly ex` tending cammlng -arms connected with said timer cam andcooperating with said camming portions, said portions and arms beingarranged so that as the weights move outwardly from the cam, the pointsof action between said portions and said arms will move toward thecamaxis; and coiled springs connecting the cam with said mem` ber, saidsprings being arranged so that the leverage thereof with respect to thespider substantially increases as the weight members move outwardly fromthe shaft.

`11. In an ignition apparatus, the combina tion with an engine drivenshaft; of a timer cam adapted to be advanced angularly relativelythereto; a weight member attached to said shaft and in driving relationto said cam, said weight member and said cam having coacting lever armsso arranged that the leverage of the weight with respect to the cam willdecrease as the cam is ad vanced; and a sprin opposing the advancing ofthe cam, the Ieverage of said spring increasing as the cam is advanced.

12. A timer for ignition apparatus com prising a retable cam, a breakerlever fulcrumed at one end upon a fixed part, and cooperating at itsopposite end with a rotatable cam, a stationary contact carried by a xedpart and located between the cam and fulcrum, a cooperating contactcarried by the breaker lever and disposed between the ends thereof, andav spring cooperating with said lever for normally maintaining the con`tacts in engagement, the leverage of said spring with respect to saidfulcrum being less than the distance from the contacts to the fulcrum.

signature.

OLIVER F. CONKLIN.

